The safety valve is a special valve that is normally closed under the action of external force, and when the medium pressure in the equipment or pipeline rises beyond the specified value, the medium is discharged outside the system to prevent the medium pressure in the pipeline or equipment from exceeding the specified value. Safety valve is an automatic valve, mainly used in boilers, pressure vessels and pipelines, control pressure does not exceed the specified value, personal safety and equipment operation plays an important role in protecting. The injection safety valve must be tested before it can be used.